VATICAN CITY -- Benedict XVI has left the Vatican for the last time as pope, flying by helicopter to the Vatican's vacation retreat hours before becoming the first pontiff to resign in 600 years.

As his closest aide wept by his side, Benedict bade farewell to Vatican officials gathered in the San Damaso courtyard of the Apostolic Palace, a corps of Swiss Guards standing by at attention.

Benedict traveled by car to the helipad on the top of the hill of the Vatican gardens and boarded a helicopter along with his secretary, Monsignor Georg Gaenswein, for the 15-minute trip to Castel Gandolfo. Bells tolled as the helicopter took off.

Before leaving, Benedict pledged his "unconditional reverence and obedience" to his successor.